Relationships of Purpose in Life with Mental Health Among Older Adults: Links to Health and Social Behaviors

Purpose in life (PIL) is often defined as how an individual experiences their life as being directed, organized, and motivated by important goals. More broadly, PIL can also be conceptualized as health and well-being, meaningful goals and purpose, inner strength, social relationships, mattering to others, and spirituality and religiousness. Many studies have shown how these PIL is associated with these positive outcomes among older adults. Older adults with high PIL have lower mortality rates and higher rates of successful aging (1). The impact of PIL on psychiatric illnesses and suicidality has not been systematically studied, however enhancing PIL may be an important consideration for high-risk groups of older adults.

The timely study by Fischer and colleagues examined PIL and its relationships to psychiatric symptoms and suicidality in a large, nationally representative group of veterans aged 60+ (Fischer citation). Within the cohort, the veterans with high PIL were older, more likely to be male, served in the military for 10+ years, and had annual household income >$60,000. The authors found that low PIL was associated with higher prevalence of depressive, anxiety, and post-traumatic stress-related symptoms; alcohol use disorder; drug use disorder; suicidal ideation, suicide attempt, and future suicidal intent; with a dose-dependent effect of PIL on most outcomes. The results suggest that PIL could be an important target and/or mediator for improving suicidality and psychiatric outcomes for a high-risk population for poor mental health.

Sex differences are an important consideration for PIL and health outcomes in older adults. In contrast to Fischer et al., some studies have reported that women have higher PIL than men (2). The veteran cohort in the current study had a low percentage of women (~ 10%), and women veterans may face unique stressors and challenges through the course of their military service. Deeper understanding of key life experiences and resiliency factors for sex differences in PIL is needed. Interestingly, PIL has been shown to have sex-specific effects on health. One study found that high PIL was protective from cardiovascular disease in only men (3). Another study reported that consistently high PIL was associated with lower risk of developing unhealthy C-reactive protein (CRP, a pro-inflammatory biomarker) levels in men only (4). These results may reflect sex-specific relationships between stress and inflammation. Mechanistic studies that are powered to examine sex differences and the influence of hormones will clarify which individuals who are most likely to benefit from PIL-focused interventions.

The possible mediating mechanisms of PIL on physical and mental health are unclear. Fischer and colleagues hypothesized that high pre-existing PIL could promote resilience and buffer against the development of psychiatric illnesses. The authors acknowledged that the reverse could also be true – psychiatric illness may erode PIL. Other theories include that individuals with high PIL are more motivated to engage in health-promoting behaviors and in adaptive coping mechanisms, e.g., proactive coping. One longitudinal cohort study from the Health and Retirement Study found that higher PIL was associated with lower incidence of pre-diabetes and Type 2 Diabetes Mellitus at 4-year follow-up (5). Though individuals with high PIL at baseline also had lower BMI, more physical activity, and better self-reported health at baseline, the longitudinal relationships were independent of BMI, physical activity, mental health, and sociodemographic factors. The data suggested that individuals with high PIL may use more preventative health services, may be more invested in caring for their health, or may feel better equipped to handle stress. Use of proactive coping strategies may translate to better well-being which is associated with decreased inflammation (6), a key mediator of age-related health outcomes.

In addition to behaviors related to physical health, PIL has also been linked to social behaviors – namely, loneliness and social supports. One study built a machine learning model based on the 1,839 older adults from Rush Memory and Aging study that found that lower PIL was associated with greater loneliness, lower perceived social support, and fewer social activities (7). Loneliness itself is associated with poor physical health outcomes and increased mortality. Studies examining pre- and post-COVID-19 pandemic cohorts have reported that high PIL was protective against loneliness, in the context of social distancing guidelines and increased stress. PIL may be intrinsically tied to social relationships as significant others, family, and close friends may be a key positive influence on PIL for older adults. Similarly, having high PIL may shape coping strategies when individuals feel lonely or socially isolated, e.g., seeking companionship rather than withdrawing from social interactions. Independent of social isolation, loneliness has strong associations with pro-social behaviors such as self-compassion and compassion for others. Humans are a social species, and PIL for many individuals may be intrinsically associated with having meaningful connections with others, feeling part of a collective humanity, and valuing altruism towards others.

PIL has the potential to positively impact aging and associated mental and physical health outcomes, though the relationships may be bidirectional. The mediating mechanisms of PIL to influence health-promoting behaviors and social behaviors are understudied. Deeper understanding of these mechanisms can influence development of targeted and effective PIL-focused interventions. Furthermore, bolstering PIL in childhood and young adulthood could prevent development of mental and physical health problems and bolster successful aging.